Field effect transistor, electrical device array and method for manufacturing those

Abstract

A field effect transistor of the present invention includes: a gate electrode formed on a substrate; a gate insulation layer formed on the gate electrode: a source electrode and a drain electrode that are formed on the gate insulation layer; a n-type semiconductor layer including carbon nanotube, formed between the source electrode and the drain electrode so as to contact with the source electrode and the drain electrode; and a n-type modifying polymer layer formed on the n-type semiconductor layer, the n-type modifying polymer layer being for converting a polarity of the carbon nanotube from an original polarity of p-type into n-type and for stabilizing the polarity. The semiconductor characteristics of CNT are converted concurrently with the formation of the semiconductor protective layer, whereby the manufacturing process can be simplified. Thereby, a CNT-FET circuit that is stable even in the air can be provided.

1 . A field effect transistor, comprising: 
 a gate electrode formed on a substrate;    a gate insulation layer formed on the gate electrode:    a source electrode and a drain electrode that are formed on the gate insulation layer;    a n-type semiconductor layer comprising carbon nanotube, formed between the source electrode and the drain electrode so as to contact with the source electrode and the drain electrode; and    a n-type modifying polymer layer formed on the n-type semiconductor layer, the n-type modifying polymer layer being for converting a polarity of the carbon nanotube from an original polarity of p-type into n-type and for stabilizing the polarity.    
     
     
         2 . The field effect transistor according to  claim 1 , wherein the n-type modifying polymer is an imine nitrogen containing polymer.  
     
     
         3 . The field effect transistor according to  claim 2 , wherein the imine nitrogen containing polymer is polyalkylene imine.  
     
     
         4 . The field effect transistor according to  claim 3 , wherein the polyalkylene imine is at least one selected from the group consisting of polyethylene imine, polypropylene imine and polybutylene imine.  
     
     
         5 . The field effect transistor according to  claim 1 , further comprising a resin protective film formed on the n-type modifying polymer layer.  
     
     
         6 . The field effect transistor according to  claim 1 , wherein the n-type modifying polymer is formed by an ink-jet method.  
     
     
         7 . An electrical element array, comprising: 
 a substrate; and    a n-type field effect transistor and a p-type field effect transistor that are formed on the substrate,    wherein the n-type field effect transistor, comprising:    a gate electrode formed on the substrate;    a gate insulation layer formed on the gate electrode:    a source electrode and a drain electrode that are formed on the gate insulation layer;    a n-type semiconductor layer comprising carbon nanotube, formed between the source electrode and the drain electrode so as to contact with the source electrode and the drain electrode; and    a n-type modifying polymer layer formed on the n-type semiconductor layer, the n-type modifying polymer layer being for converting a polarity of the carbon nanotube from an original polarity of p-type into n-type and for stabilizing the polarity,    wherein the p-type field effect transistor, comprising:    a gate electrode formed on the substrate;    a gate insulation layer formed on the gate electrode:    a source electrode and a drain electrode that are formed on the gate insulation layer; and    a p-type semiconductor layer comprising carbon nanotube, formed between the source electrode and the drain electrode so as to contact with the source electrode and the drain electrode.    
     
     
         8 . The field effect transistor according to  claim 7 , wherein the n-type modifying polymer is an imine nitrogen containing polymer.  
     
     
         9 . The field effect transistor according to  claim 8 , wherein the imine nitrogen containing polymer is polyalkylene imine.  
     
     
         10 . The field effect transistor according to  claim 9 , wherein the polyalkylene imine is at least one selected from the group consisting of polyethylene imine, polypropylene imine and polybutylene imine.  
     
     
         11 . The field effect transistor according to  claim 7 , further comprising a resin protective film formed on the n-type modifying polymer layer.  
     
     
         12 . The field effect transistor according to  claim 7 , wherein the n-type modifying polymer is formed by an ink-jet method.  
     
     
         13 . The electrical element array according to  claim 7 , further comprising a protective layer made of an imine nitrogen not-containing polymer formed on the p-type semiconductor layer.  
     
     
         14 . The electrical element array according to  claim 13 , wherein the imine nitrogen not-containing polymer is at least one selected from the group consisting of an acrylic resin, an epoxy resin, polyolefin, polyester, polycarbonate, polystyrene, polyacrylonitrile, polyvinylidene fluoride, polyvinylidene cyanide and polyvinyl alcohol.  
     
     
         15 . The electrical element array according to  claim 13 , wherein the n-type modifying polymer and the imine nitrogen not-containing polymer are formed by an ink-jet method.  
     
     
         16 . A method for manufacturing a field effect transistor, comprising the steps of: 
 forming a gate electrode on a substrate;    forming a gate insulation layer on the gate electrode;    forming a source electrode and a drain electrode on the gate insulation layer;    forming a semiconductor layer comprising carbon nanotube on the gate insulation layer and between the source electrode and the drain electrode; and    forming a n-type modifying polymer layer on the semiconductor layer by dispensing with an ink-jet method, the n-type modifying polymer layer being for converting a polarity of the carbon nanotube from an original polarity of p-type into n-type and for stabilizing the polarity.    
     
     
         17 . The method for manufacturing a field effect transistor according to  claim 16 , wherein the n-type modifying polymer is an imine nitrogen containing polymer.  
     
     
         18 . The method for manufacturing a field effect transistor according to  claim 17 , wherein the imine nitrogen containing polymer is polyalkylene imine.  
     
     
         19 . The method for manufacturing a field effect transistor according to  claim 18 , wherein the polyalkylene imine is at least one selected from the group consisting of polyethylene imine, polypropylene imine and polybutylene imine.  
     
     
         20 . A method for manufacturing an electrical element array including a n-type field effect transistor and a p-type field effect transistor on a substrate, comprising the steps of: 
 forming a gate electrode on a substrate;    forming a gate insulation layer on the gate electrode;    forming a source electrode and a drain electrode on the gate insulation layer;    forming a semiconductor layer comprising carbon nanotube on the gate insulation layer and between the source electrode and the drain electrode; and    forming a n-type modifying polymer layer only on a part of the semiconductor layer that should be converted into n-type by dispensing in an ink-jet method, the n-type modifying polymer layer being for converting a polarity of the carbon nanotube from an original polarity of p-type into n-type and for stabilizing the polarity.